code: def mask_array(array):
      """Mask an array with nan instead of 0."""
      return np.where(array == 0, np.nan, array)
  
imports: import os
  from datetime import datetime
  import dask.array
  import h5netcdf
  import numpy
  import pytest
  from satpy import Scene
  from satpy.readers.insat3d_img_l1b_h5 import CHANNELS_BY_RESOLUTION, LUT_SUFFIXES, Insat3DIMGL1BH5FileHandler, get_lonlat_suffix, open_dataset, open_datatree
  from satpy.tests.utils import make_dataid
label_desc: Use image node_id 2 for calling a global function with example usage: mask_array(array) and returns: np